NASA wants to send HEDGEHOGS to Mars

'Test pilot' survives vomit comet

Video The space-makers at JPL are toying with the idea of getting rid of wheels for planetary exploration robots. Instead, the “hedgehog” design in the pic above (here for mobile readers) exploits low gravity environments to get around without them.

Nicknamed “Hedgehog”, the robot is a joint project with the Jet Propulsion Laboratory, Stanford University, and MIT.

So far, the groups have built two prototypes, one by Arnold JPL, the other by Kendall Stanford.

The bots move using a combination of flywheels and spikes. Starting and stopping the flywheels (using disk brakes in the JPL prototype, or friction belts in the Stanford unit) controls manoeuvring, while the spikes provide the energy for larger movements.

So far, two prototypes of Hedgehog exist: one from JPL weighing 5 kg (11 pounds), and a slightly lighter Stanford version with shorter spikes.

So as the devices aren't blinded by a bad landing, they're designed so it doesn't matter which face is “down”. The cube shape is also convenient for packaging on a spacecraft, easy to manufacture, and provides the best “hopping” performance.

The tests covered materials that “mimic a wide range of surfaces: sandy, rough and rocky, slippery and icy, and soft and crumbly”, NASA says.

The moves start with a way – an in-place turn – and go all the way up to a “tornado” if the robot had to escape from somewhere like a sandy sinkhole.

If NASA sends one of these to an asteroid and doesn't call it “Sonic”, NASA could well crash the Internet. ®